Giovanni's father Pietro II Orseolo was the Doge of Venice, and his mother was Maria Candiano.
Under this agreement the Venetians would conquer Dalmatia and then hold it as a protectorate under Byzantine suzerainty.
[1] While in Constantinople he was given a standard to use in his upcoming invasion of Dalmatia by the Bishop of Olivolo.
He was successful in establishing Venetian power on the Dalmatian coast.
In 1004 Giovanni married Maria Argyre, who was probably niece of Basil II and relative to the latter's second cousin and future emperor Romanos III Argyros.